Breakaway valve

ABSTRACT

A frangible or breakaway valve for use in a flexible tube. The valve comprises two parts: a tubular portion with a closed end and an elongated, generally rigid handle breakably attached to the closed end. The elongated handle has projections which frictionally contact the interior surface of the flexible tube and prevent the elongated handle from moving back into a closed position once the elongated handle has been broken. The valve may be used in conjunction with tubing and a plastic container of dialysis solution. The valve is opened by breaking away the elongated, generally rigid handle and moving &#34;walking&#34; the rigid handle down the tube by folding the tube back and forth upon itself. The projections on the rigid breakaway handle have sufficient frictional contact with the inside of the tube to assure that the handle will not move back into contact with the tubular portion, and the valve will remain open.

BACKGROUND OF THE INVENTION

This invention relates to an improved frangible or breakaway valve in aflexible circular tube, principally for use in conjunction with aperitoneal dialysis solution container or blood bag.

Currently, the most widely used method of kidney dialysis for treatmentof End Stage Renal Disease (ESRD) is "hemodialysis". Here, the patient'sblood is cleansed by passing it through an artificial kidney in anartificial kidney dialysis machine. By the process of diffusion across asemipermeable membrane in the artificial kidney, impurities and toxinsare removed from the patient's blood to thereby perform a function ofthe patient's natural kidneys. Hemodialysis is required several times aweek, each dialysis requiring several hours in a dialysis center or athome. During dialysis, the patient is "tied" to the machine by venousand arterial blood lines which convey his blood to and from theartificial kidney.

Although used less frequently than hemodialysis, a procedure known as"intermittent peritoneal dialysis" is an accepted method for treatingESRD. In this procedure, a dialysis solution is infused into thepatient's peritoneal cavity by means of tubing and a catheter. Theperitoneum, which defines the peritoneal cavity, contains many smallblood vessels and capillary beds which act as a natural semipermeablemembrane. This natural membrane may be contrasted with the artificialmembrane used in hemodialysis. In both cases, however, impurities andtoxins in the blood are removed by diffusion across a membrane--acellulose membrane of an artificial kidney or a peritoneal membrane of aperitoneal cavity.

In intermittent peritoneal dialysis, dialysis solution remains in thepatient's peritoneal cavity for a time sufficient for blood impuritiesto be removed by diffusion across the peritoneal membrane into thedialysis solution. The impurity containing dialysis solution then isdrained from the peritoneal cavity by means of the catheter and tubing,and a fresh supply of dialysis solution is infused. Intermittentperitoneal dialysis utilizes pumps or other auxiliary equipment to whichthe patient is "tied" during dialysis; here also the patient must remainsedentary.

Continuous ambulatory peritoneal dialysis is another type of peritonealdialysis which uses the peritoneum as a semipermeable membrane. Thisprocedure has the important advantage, however, of enabling the patientto be ambulatory and conduct a normal routine during dialysis. Thepatient is not "tied" to a machine and he must be sedentary only for thetime period required to drain and infuse dialysis solution from and intothe peritoneal cavity. This infusion and draining is handled by tubingand a surgically implanted, indwelling catheter in the patient'sabdominal wall and in communication with his peritoneal cavity.

The continuous ambulatory peritoneal dialysis procedure is intended tobe a patient self-care technique once the catheter is surgicallyimplanted. Thus, it is important that the apparatus involved, e.g.,tubing and solution container, be simple and easy to use. The presentinvention is intended to simplify the procedure for infusing dialysissolution into the peritoneal cavity. The invention concerns a novelbreakaway valve in the tubing which is attached to or may be a part ofthe peritoneal dialysis solution container.

Breakaway valves in flexible tubes for use in blood bags are known inthe art. The prior art valves typically consist of two parts: a hollowtubular portion bonded to the interior of a flexible tube and a rigidbreakaway portion or handle integral with the hollow tubular portion.The handle is breakable by manual manipulation. After breaking, it movesaway from its interface with the tubular portion and fluid can flow pastit and through the tubing.

An example of a frangible valve in a blood bag is shown in Yoshino U.S.Pat. No. 4,007,738. Here the valve is opened by manually breaking areduced annular section to effect fluid flow within the blood bagtubing, the breakaway portion floating freely within the tube. Anotherfrangible valve used in a blood bag is shown in French Pat. No.2,098,873. Here the breakaway portion falls into the blood bag. In U.S.Pat. No. 4,181,140 of Edward L. Bayham, et al.; U.S. patent applicationSer. No. 15,395 of Carter, et al., filed Feb. 26, 1979; and U.S. patentapplication Ser. No. 64,952 of Elvis E. Adams filed Aug. 8, 1979, allowned by the assignee of this application, frangible valves for flexibletubes in conjunction with blood bags are disclosed. These two patentapplications and the patent show frangible valves of variousembodiments, some with locking hold-open means. In all prior artbreakaway valves, fluid flow is in one direction only. The force of thefluid flow tends to push the broken away part of the valve away from theopening. In practicing the continuous ambulatory peritoneal dialysisprocedure fluid flow will be in two directions--one direction duringinfusion, and the opposite direction during drain.

Some disadvantages of the known frangible valves include: (1) theinability to assure that the breakaway portion will remain in an openposition after being broken, (2) the complex configuration required tolock the breakaway portion in a hold-open position, and (3) thedifficulty in manually breaking the valve and moving it to an openposition. The latter disadvantage is particularly significant when aperson does not have good manual dexterity or strength.

Thus, there is a need to provide a frangible valve in a flexible tubewhich can be easily broken and moved to and remain in an open position.A valve configuration which is simple in design is also desirable forease of molding and manufacture.

With the advent of dialysis solutions contained in plastic bags, and thedevelopment of continuous ambulatory peritoneal dialysis, a simplefrangible valve for use by patients in establishing flow from aperitoneal dialysis solution bag via tubing and a catheter to thepatient's peritoneal cavity is desired. A simple effective frangiblevalve which after breaking will remain locked in a hold-open positionwould, in addition to its potential use in blood bags, be important,particularly from a patient self-care standpoint, when practicingcontinuous ambulatory peritoneal dialysis. It is, therefore, an objectof this invention to provide an improved frangible valve in a flexibletube which has a simple, effective hold-open feature for use inperitoneal dialysis solution bags for continuous ambulatory peritonealdialysis patients, is easy to open, and easy to move to a hold-openposition.

Breaking of the valve of this invention is done by bending the exteriorof the flexible, circular tubing back upon itself at the point where thehandle joins the closed end of the tubular portion. The initial bendingaction, and subsequent bending, will "walk" the handle down the tube andaway from the now opened tubular portion. Ease of breaking is importantfor the practice of continuous ambulatory peritoneal dialysis because ofthe large number of patients with limited physical capacity because ofpoor eyesight, weakness, arthritis and the like. This invention also isparticularly advantageous for use by children and geriatric patients forthese same reasons.

The valve of this invention remains in a hold-open position because ofprojections on the handle. They frictionally contact the interior of theflexible tube; they tightly grip or "bite" into the soft, flexibletubing. Some of the known breakaway valves used in blood bags haveprovided for frictional contact at a special reduced conical section inthe tube. The valve of this invention eliminates the need for anyspecial insert or section (conical, or otherwise) in the tube to holdthe broken away handle. The size of the flexible, circular tubing canremain constant, unlike existing blood bag valves with hold-open meansin which the valve is locked into a conical section of tubing of reducedcross section.

SUMMARY OF THE INVENTION

The frangible valve of the present invention comprises two integralparts: an elongated, generally rigid handle and a tubular portion with aclosed end integral with the handle. The elongated handle carriesoutwardly extending projections for frictional contact with the interiorsurface of a flexible circular tube. A frangible zone of weakness islocated at the junction of the tubular portion and the elongated handle.When broken by exterior manipulation, the handle moves away from thetubular portion and takes a portion of the closed end with it, therebypermitting flow in the tube.

The frangible zone of weakness may be an annular line of tearingweakness, or may result from the geometry of the tubular portion andhandle without need for a specially formed line of tearing weakness. Thepreferred valve is breakable by exterior manual manipulation,accomplished by bending the flexible tube back upon itself causing therigid breakaway handle to "walk" down the flexible tube away from thevalve opening.

As the rigid handle is broken away in the tube, the handle is "walked"down in frictional contact with the interior surface of the tube. Thisallows the valve to remain in an open position and permits uninterruptedfluid flow as the projections on the handle "bite" into the tube andprevent the handle from moving back toward the previously closed end.The position of the handle remains fixed regardless of the direction offluid flow through the valve in the tube. The frictional contact issufficient to prevent the valve from accidentally closing because of the"biting" action of the projections on the handle. The frictional fit ofthe projections within the flexible tube is a simple means of assuringthat the valve remains open, this simplicity distinguishing it fromprior valves which lock in an open position by means of a lockingconfiguration difficult to fabricate and which because of their designcan only be assured to permit uninterrupted flow in one direction.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects, features and advantages of the present invention willbecome more fully apparent from the following detailed description ofthe preferred embodiment, the appended claims and the accompanyingdrawings in which:

FIG. 1 is a view of a solution container for using the valve of thepresent invention in the outlet port of the container;

FIG. 2 is a greatly enlarged view of the preferred embodiment of thevalve of this invention, in conjunction with the solution container ofFIG. 1, with some of the parts shown in longitudinal section;

FIG. 3 shows the valve in the open position;

FIG. 4 is a perspective view, with portions broken away, of the valve ofthis invention;

FIG. 5 is an end view of the valve of this invention viewed from theelongated, generally rigid handle to the tubular portion;

FIG. 6 is a fragmentary, perspective view showing a tube integral with asolution container, a portion of the tube shown in cross section, thevalve of this invention in the tube shown being opened by manualexterior manipulation;

FIG. 7 is a view of an alternative embodiment of the valve of thisinvention in a flexible tube, with some of the parts shown inlongitudinal section; and

FIG. 8 is an end view of the embodiment of FIG. 7 showing the elongated,generally rigid handle in frictional contact with the interior of aflexible tube.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The preferred embodiment of the valve of this invention is illustratedby way of example in FIGS. 2-5. FIG. 1 shows the valve in a preferredembodiment, that is, the outlet port of a peritoneal dialysis solutioncontainer. The valve may be positioned, however, anywhere within thetubing connecting the dialysis solution container to the catheterimplanted in the patient.

Referring to FIG. 1, a peritoneal dialysis solution container 10 isshown with a tubular outlet port 12 and a tubular medication injectionport 14; both ports are in communication with the inside of the solutioncontainer 10. The frangible valve of the invention is shown interiorlyfitted in port 12. It has a tubular portion 24 and an elongated,generally rigid handle 28 extending from and integral with the closedend 26 of tubular portion 24. Tubular portion 24 is sealed into outletport 12 by means of a solvent bonding, heat bonding or other bondingtechniques known in the art.

Referring to FIGS. 2-5, the valve is shown by way of example with aperitoneal dialysis solution container 10 which has a flat seal 20 whichseals a flexible circular tube 22 (port 12 of FIG. 1) in communicationwith the interior of container 10.

Sealed within the distal end of flexible tube 22 is a tubular portion24, having a closed end 26. Closed end 26 has extending from andintegral with it an elongated, generally rigid handle 28. Closed end 26has an annular zone of weakness 27 to facilitate breaking the handle 28from tubular portion 24 thereby opening the valve. Tubular portion 24and handle 28, which form the valve, are preferably a molded, chemicallyinert, rigid plastic. The plastic of the preferred embodiment ispolyvinyl chloride.

Handle 28 includes a plurality of outwardly extending projections 30which frictionally fit within the interior of flexible tube 22.Projections 30 dig into the interior of tube 22 and hold the handle 28in position after it is broken away from closed end 26. This assuresthat fluid can flow in two directions, one way for infusion of dialysissolution and the opposite way for drainage, without the handle movingback into contact with the closed end 26 and blocking flow. Thefrictional fit of the handle projections 30 in the walls of tube 22distinguish the valve of this invention from prior art valves.

The valve of the present invention may be opened manually bymanipulating flexible tube 22 at the valve's annular zone of weakness27. By bending flexible tube 22 back upon itself at the valve's annularzone of weakness 27, handle 28 is broken away from tubular portion 24and takes a portion of closed end 26 with it. Continued bending moveshandle 28 toward the proximal end of tube 22, in effect, "walking" ittoward solution container 10. The frictional projections 30 are spacedfrom each other to avoid adversely affecting fluid flow within theflexible tube.

The valve could also be oriented in the tube 22 such that the handlewould be walked away from, rather than toward, the container 10.

Referring to FIG. 6, a partial perspective view is shown with tube 22shown in partial cross section. Hands are shown bending the tube 22 tobreak handle 28 from the valve. Tubular portion 24 of the valve remainsin place within flexible tube 22 since it is bonded to the interior offlexible tube 22. Outwardly extending projections 30 of rigid handle 28maintain frictional contact with the interior of flexible tube 22 as thevalve is opened and the rigid handle is "walked" down the tube by manualbending and releasing of flexible tube 22. The force created by foldingthe tubing back upon itself "walks" handle 28 down tube 22 where itremains after the force is released. Handle 28 can be "walked" furtherdown tube 22 by again folding tube 22 back upon itself and releasing.Projections 30 assure that the handle 28 will remain away from the valveopening by frictionally "biting" into the flexible tube 22.

Referring to FIGS. 7 and 8, an alternative embodiment of the inventionis shown bonded within a flexible tube 32. The valve has a tubularportion 34 with a conical section 36 thereof of reduced cross sectionand closed end 38. An elongated, generally rigid handle 40 extends fromclosed end 38. It has a plurality of projections 42 which frictionallycontact the interior of tube 32. The closed end 38 has an annular zoneof weakness 39 to aid in opening the valve. Extending parallel to thelongitudinal axis of handle 40 from the portion of the handle carryingprojections 42 is a generally rigid, elongated member 44 which aids intearing away at the zone of weakness 39 by giving leverage to thepatient to break the valve open. It is easier for weak or elderlypatients to open this embodiment of the valve because of the mechanicaladvantage gained by the member 44 and annular zone of weakness 39. Thetubing 32, as in the previously described embodiment, is bent back uponitself to cause generally rigid, elongated handle 40 to "walk" towardthe proximal end of tube 32.

The present invention provides an improved valve in a flexible tubewhich can be easily manually manipulated for the purpose of opening thevalve to allow flow through the tube. The valve remains in the openposition by means of projections on the rigid handle of the valve"biting" into the flexible tube. In addition, because of the design ofthe valve, a simple method can be used to effect its opening by bendingat the junction of the handle and the closed end of the tubular portion.The tube is bent back upon itself to cause the generally rigid handle ofthe valve to move or "walk" away from the tubular portion of the valve.Thus, the valve of the present invention has an important advantage ofsimplicity in design in using frictional contact to remain open. It alsohas the advantage of a simplified patient method for opening andassuring the continued open position of the valve.

While the present invention has been disclosed in connection with thepreferred embodiment thereof and an alternative embodiment thereof, itshould be understood that there may be other embodiments, which fallwithin the sphere and scope of the invention as defined by the followingclaims.

What is claimed is:
 1. A valve inside a flexible tube whichcomprises:(a) a tubular portion having a closed end to prevent fluidflow in the tube; (b) a handle extending from and integral with theclosed end of the tubular portion; (c) a zone of weakness positionedwhereby at least a portion of the closed end is removable bymanipulating the handle to separate said closed end from the tubularportion to permit fluid flow through the valve; and (d) projection meansradially outwardly extending from the handle, said projection meanshaving sufficient frictional contact with the interior surface of theflexible tube so that after separation of the handle from the tubularportion the handle can be moved away from the tubular portion and remainin any selected position in the tube, away from the tubular portion, toassure uninterrupted fluid flow.
 2. The valve of claim 1 in which thetubular portion is sealed to the inside of the flexible, circular tubeby heat bonding.
 3. The valve of claim 1 in which the tubular portion issealed to the inside of the flexible, circular tube by solvent bonding.4. The valve of claim 1 in which said zone of weakness is at thejunction of the handle and closed end.
 5. In a peritoneal dialysissolution container having at least one tube communicating with theinterior of the container, a valve positioned in said tube, the valvecomprising:(a) a tubular portion with a closed end wall; (b) anelongated handle integral with the closed end wall; (c) a zone ofweakness positioned whereby at least a portion of the closed end isremovable by manipulating the handle to separate said closed end fromthe tubular portion to permit fluid flow through the valve; and (d)projection means radially outwardly extending from the handle, saidprojection means being frictionally in contact with the interior surfaceof the tube so that after separation of the handle from the tubularportion the handle can be moved away from the tubular portion and remainin any selected position in the tube, away from the tubular portion, toassure uninterrupted flow.
 6. The valve of claim 5 in which theelongated, generally rigid handle has extending therefrom, parallel tothe longitudinal axis of the handle, a rigid member to ease separationof the handle from the tubular portion permitting flow in the tube. 7.The solution container of claim 5 in which said zone of weakness is atthe junction of the handle and closed end.
 8. In the combination of adialysis solution container, flexible tubing connected to the dialysissolution container, the tubing connected to a catheter implanted in apatient's peritoneal cavity, and a valve in the tubing, said valvecomprising:(a) a tubular portion with a closed end wall; (b) a handleextending from and integral with the closed end wall of the tubularportion; (c) a zone of weakness positioned whereby at least a portion ofthe closed end is removable by manipulating the handle to separate saidclosed end from the tubular portion to permit fluid flow through thevalve; and (d) projection means radially outwardly extending from thelongitudinal axis and periphery of the handle, said projection meanshaving sufficient frictional contact with the interior surface of theflexible tubing so that after separation of the handle from the tubularportion, the handle can be moved away from the tubular portion andremain in any selected position in the tubing, away from the tubularportion, to assure uninterrupted fluid flow.
 9. The combination of claim8 in which the zone of weakness is at the junction of the handle andclosed end wall.